<?php
/**
 * Post is an instance of CActiveRecord (sytem.db.ar). 
 *
 * CActiveRecord is the base class for classes representing relational data. 
 *
 * Eduow :  International system for education (http://www.eduow.com)
 * Copyright 2010, Nikolay Stoitsev
 *
 * Licensed under GNU General Public License version 2
 * Redistributions of files must retain the above copyright notice.
 *
 * @filesource
 * @copyright     Copyright 2010
 * @link          http://eduow.com Eduow Project
 * @package       eduow
 * @subpackage    application.models
 * @inheritance   class Post >> CActiveRecord >> CModel >> CComponent
 * @implements    ArrayAccess, Traversable, IteratorAggregate
 * @since         Eduow v 0.0.4
 * @license       http://www.gnu.org/licenses/gpl-2.0.html GNU General Public License version 2
 */

class Post extends CActiveRecord
{
	/**
	 * The followings are the available columns in table 'post':
	 * @var integer $id
	 * @var string $title
	 * @var string $content
	 * @var string $tags
	 * @var integer $status
	 * @var integer $create_time
	 * @var integer $update_time
	 * @var integer $author_id
	 */
	const STATUS_DRAFT=1;
	const STATUS_PUBLISHED=2;
	const STATUS_ARCHIVED=3;

	private $_oldTags;

	/**
	 * Returns the static model of the specified AR class.
	 * @return CActiveRecord the static model class
	 */
	public static function model($className=__CLASS__)
	{
		return parent::model($className);
	}

	/**
	 * @return string the associated database table name
	 */
	public function tableName()
	{
		return 'post';
	}

	/**
	 * @return array validation rules for model attributes.
	 */
	public function rules()
	{
		return array(
			array('title, content, status, category_id', 'required'),
			array('status', 'in', 'range'=>array(1,2,3)),
			array('title', 'length', 'max'=>128, 'min'=>2),
			array('tags', 'match', 'pattern'=>'/^[a-zA-Zа-яА-Я1-9, ]+$/u', 'message'=>Yii::t('yii','Tags can only contain word characters.')),
			array('tags', 'normalizeTags'),
			array('category_id, language','safe'),
		);
	}

	/**
	 * @return array relational rules.
	 */
	public function relations()
	{
		return array(
			'author' => array(self::BELONGS_TO, 'User', 'author_id'),
			'comments' => array(self::HAS_MANY, 'Comment', 'post_id', 'condition'=>'comments.status='.Comment::STATUS_APPROVED, 'order'=>'comments.create_time DESC'),
			'commentCount' => array(self::STAT, 'Comment', 'post_id', 'condition'=>'status='.Comment::STATUS_APPROVED),
		);
	}

	/**
	 * @return array customized attribute labels (name=>label)
	 */
	public function attributeLabels()
	{
		return array(
			'id' => Yii::t('yii','Id'),
			'title' => Yii::t('yii','Title'),
			'content' => Yii::t('yii','Content'),
			'tags' => Yii::t('yii','Tags'),
			'status' => Yii::t('yii','Status'),
			'create_time' => Yii::t('yii','Create Time'),
			'update_time' => Yii::t('yii','Update Time'),
			'author_id' => Yii::t('yii','Author'),
			'category_id' => Yii::t('yii','Category'),
			'language' => Yii::t('yii','Language'),
		);
	}

	/**
	 * @return string the URL that shows the detail of the post
	 */
	public function getUrl()
	{
		return Yii::app()->createUrl('post/view', array(
			'id'=>$this->id,
			'title'=>$this->title,
		));
	}

	/**
	 * @return array a list of links that point to the post list filtered by every tag of this post
	 */
	public function getTagLinks()
	{
		$links=array();
		foreach(Tag::string2array($this->tags) as $tag)
			$links[]=CHtml::link(CHtml::encode($tag), array('post/index', 'tag'=>$tag));
		return $links;
	}

	/**
	 * Normalizes the user-entered tags.
	 */
	public function normalizeTags($attribute,$params)
	{
		$this->tags=Tag::array2string(array_unique(Tag::string2array($this->tags)));
	}

	/**
	 * Adds a new comment to this post.
	 * This method will set status and post_id of the comment accordingly.
	 * @param Comment the comment to be added
	 * @return boolean whether the comment is saved successfully
	 */
	public function addComment($comment)
	{

		$comment->status=Comment::STATUS_PENDING;

		$comment->post_id=$this->id;
		return $comment->save();
	}

	/**
	 * This is invoked when a record is populated with data from a find() call.
	 */
	protected function afterFind()
	{
		parent::afterFind();
		$this->_oldTags=$this->tags;
	}

	/**
	 * This is invoked before the record is saved.
	 * @return boolean whether the record should be saved.
	 */
	protected function beforeSave()
	{
		if(parent::beforeSave())
		{
			if($this->isNewRecord)
			{
				$this->create_time=$this->update_time=time();
				$this->author_id=Yii::app()->user->id;
				$this->language=Yii::app()->language;
			}
			else
				$this->update_time=time();
			return true;
		}
		else
			return false;
	}

	/**
	 * This is invoked after the record is saved.
	 */
	protected function afterSave()
	{
		parent::afterSave();
		Tag::model()->updateFrequency($this->_oldTags, $this->tags);
	}

	/**
	 * This is invoked after the record is deleted.
	 */
	protected function afterDelete()
	{
		parent::afterDelete();
		Comment::model()->deleteAll('post_id='.$this->id);
		Tag::model()->updateFrequency($this->tags, '');
	}
}
